The bacterial enteropathogen Salmonella is able to establish infection by injecting bacterial effector proteins into the host cell through a specialized organelle called the type three secretion system (TTSS). One class of effectors manipulate Rho-family GTPases to promote bacterial internalization. Other effectors promote the biogenesis of a membrane-bound compartment in which Salmonella resides and replicates. This compartment avoids fusion with the lysosome, yet acquires a subset of host proteins. The focus of my research is to understand the events that lead to the formation and maintenance of this replicative niche. I will explore the membrane trafficking events that transform and enlarge this compartment and identify specific salmonella TTSS effector proteins that control this process. Understanding how Salmonella exploits the host exocytic and endocytic machinery may lead to the development of novel strategies to combat Salmonella infection.